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Boletus edulis is fairly easy to identify. One of the common features of all the varieties are the chicken wire like reticulation on the stem at its apex (think of the reticulated giraffe, the pattern on the common giraffe is what is called reticulate). It will have a bronze coloured cap with a white or yellow underside and stem. Some may have a slightly green tint but they will never be red.

The fruit body consists of a large and imposing brown cap which can reach 25 cm (10 in) in diameter and 1 kg (2.2 lb) in weight. Like other boletes, it has tubes/pores extending downward from the underside of the cap, rather than gills; spores are released at maturity through the tube openings, or pores. The pore surface of the B. edulis fruit body is whitish when young, but ages to a greenish-yellow. The stout stipe, or stem, is white or yellowish in colour, up to 25 cm (10 in) tall and 7 cm (2.8 in) thick, and partially covered with a raised network pattern, or reticulations.

The fruit bodies can grow singly or in small clusters of two or three specimens. The mushroom’s habitat consists of areas dominated by pine (Pinus spp.), spruce (Picea spp.), hemlock (Tsuga spp.) and fir (Abies spp.) trees, although other hosts include chestnut, chinquapin, beech, Keteleeria spp., Lithocarpus spp., and oak. The fungus forms symbiotic associations with living tree roots, and produces spore-bearing fruit bodies above ground in summer and autumn (they can be difficult to find being hidden amongst fallen needles / leaves).

Although fruit bodies may appear any time from summer to autumn, their growth is known to be triggered by rainfall during warm periods of weather followed by frequent autumn rain with a drop in soil temperature. Above average rainfall may result in the rapid appearance of large numbers of boletes, in what is known as a “bolete year”. Studies have concluded that the maximal daily growth rate of the cap (about 21 mm or 0.8 in) occurs when the relative air humidity is greatest, and the fruit bodies ceased growing when the air humidity dropped below 40%. Factors most likely to inhibit the appearance of fruit bodies included prolonged drought, inadequate air and soil humidity, sudden decreases of night air temperatures, and the appearance of the first frost.

The flavour has been described as nutty and slightly meaty, with a smooth, creamy texture, and a distinctive aroma reminiscent of sourdough. Young, small porcini are most appreciated as the large ones often harbor maggots and become slimy, soft and less tasty with age. Peeling and washing are not recommended. The fruit bodies are highly perishable, due largely to the high water content (around 90%), the high level of enzyme activity, and the presence of a flora of microorganisms. When you cut them lengthways – the insides remain white. The underside of the cap is always sponge like on a Cep.

Fruit bodies are collected by holding the stipe near the base and twisting gently. Cutting the stipe with a knife may risk the part left behind rotting and the mycelium being destroyed.

In Elverdinge (Ypres) during an excursion of the Mushroom Task Force West FlandersHygrocybe viola was discovered. It is the first observation of this species in Flanders. Across Europe there are only a handful of reports of this mushroom with its lilac-colored hat.

In Belgium one other discovery was made of the rare Hygrocybe viola: in 1977, in Vencimont (Wallonia). There are only a handful of known observations in the Netherlands, the United Kingdom and Denmark (Boertmann, 2010). That makes Hygrocybe viola one of the rarest of the scions of the waxcap family.

Identifying the two large sawbills, Goosander and Red-breasted Merganser, can be pretty straight-forward when confronted with male birds. However, the females, or redheads as they are more often called, can be much more difficult. This, the latest ID video gives useful pointers on how to confidently tell them apart.

Saturday 20 December was a stormy day. Usually, days like that are not really good for birdwatching. Birds tend to hide more than usually. We went to the Amsterdamse Waterleidingduinen. Would we see goosanders, beautiful birds sometimes wintering here? Would rain contribute to wind in making birding difficult?

The answer to the second question is no, it stayed dry. For an answer to the first question, keep reading :)

During an excursion by a Dutch waxcap study group on the ground layer of a fortress belonging to the Defence Line of Amsterdam many very rare bitter waxcaps were discovered. They spoke about hundreds of specimens. Such a number is unique both for the Netherlands and abroad.

During an excursion to the coastal dunes south of Ijmuiden members of Mushrooms Workgroup “The Noordkop” discovered many Hohenbuehelia fungi. After identification this turned out to be the very rare and endangered Hohenbuehelia culmicola. The fungi grew on the southern slope of a coastal sand dune.

Rarity

At global level, Hohenbuehelia culmicola is confined to the coasts of Western Europe. Until now this species had been found in the Netherlands, Germany, Denmark, Ireland, Great Britain, France and Belgium but every time these were only a few discoveries by country. The Dutch sites are therefore of great international importance.

Hohenbuehelia culmicola was only described in 1979 for the first time for the dunes of northwestern France by the French mycologist M. Bon. In 1984, Hohenbuehelia culmicola was first discovered in the Netherlands in the Kwade Hoek on Goeree island.

A close look inside the “freeways” of fungus that efficiently transport nutrients: here.

As part of the Drenthe Atlas Project Mushrooms Workgroup Drenthe (PWD) from 1999 on has examined Drenthe everywhere in all corners. It showed the importance of some forests with Norway spruce for a range of rare and endangered mushrooms. Also downright spectacular mushrooms were found, like goatcheese webcap and Psathyrella caputmedusae, which were thought to be extinct. And olive wax cap, which had been found only once before in the Netherlands.

Already in 2001 the supposedly extinct goatcheese webcap (Cortinarius camphoratus) had been found in a dark, damp and mossy plot with sixty years old Norway spruce in Grolloo forestry district.